A filler neck and a motor vehicle having a filler neck are fundamentally known from the prior art. For example, German Patent Publication No. DE 30 27 002 A1 discloses a tank filler neck arrangement for this purpose, in particular for motor vehicles. A filler neck composed of plastic and a closure base composed of metal in a concentric arrangement. The filler neck is enclosed by the closure base with pressure. For this purpose, the filler neck is supported by an inner supporting sleeve which lies under the closure base. Moreover, a ring seal which is active between both parts is arranged in a receiver in the closure base or the filler neck.
The different materials used for the filler neck have different material properties (e.g. thermal expansion coefficients, swelling characteristics as a result of the action of fuel, etc.). As a result of the influence of the fuel and/or as a result of the influence of higher temperatures, both the filler neck and also the seal may swell up and partially significantly deform over time, as a result of which tolerances are exceeded/undershot and leaks, in particular in the region of the ring seal, may arise. The imperviousness of the system may then no longer be ensured with adequate quality. In particular, stricter legal requirements in terms of hydrocarbon emissions in the case of fuel tanks cannot be satisfied over the entire lifetime of a motor vehicle.